It is commonly known that conventional wooden fences have several inherent negative characteristics. These include relatively high cost, short life expectancy due to susceptibility to rot, tendency to rapidly discolor, and natural imperfections such as knots which almost completely preclude a wooden fence from functioning as an effective privacy fence. In addition, many persons erroneously believe that owning a natural wooden fence is the correct ecological choice. However, comparable alternatives in plastic have substantially greater durability and life expectancy. Such materials (e.g. phenolics, polyimides, polypropylene, polystyrene, rubber and vinyl polymers including PVC (polyvinyl chloride)) are available which effectively resist cracks, chipping, peeling, discoloration, solar-radiative embrittlement, chemical attack and fires. In addition, because of their durability and recyclability, such alternatives do not directly contribute to the destruction of our national forests. This should be compared with the fact that an old and rotten wooden fence cannot be recycled. Further, many new wooden fences will require replacement within twelve to twenty years, thereby necessitating the ongoing destruction of our forest lands.
Although wooden fences are more natural and organic in appearance than fences constructed of artificial materials, current technology is capable of providing an convincingly wooden appearance to plastic material by embossing, forming or molding a well defined wood grain texture to such materials. Such materials may be molded with pigmented material in any of an almost unlimited range of colors which can be selected to simulate wood convincingly. These plastic materials, because they are produced by tightly controlled and repeatable processes, are made with few visible imperfections and almost no voids or pores which might otherwise compromise the effectiveness of the fence as a privacy screen. These processes (extrusions for example) produce intricate shape of accurate size which enable excellent repeatability such that mating parts fit together with relative precision.
Lowry U.S. Pat. No. 4,477,058 describes a fence constructed of plastic components whose functions includes that of a privacy fence. However, because each plastic board abuts and does not overlap or interlock with an adjacent board, gaps still exist between boards. In addition, the gaps may easily become enlarged if any bowing or warping occurs in adjacent boards. Therefore, it is still relatively easy for a curious person to peer between the slats to obtain a view of events taking place on the other side. Although an improvement over wooden fences in that it is made of durable material and does not contain the knots, it is not completely effective as a privacy fence.
Pepper U.S. Pat. No. 5,255,897 describes a privacy fence made of plastic. However, adjacent vertical slats do not interlock. This creates gaps or "elongated spaces" between adjacent slats into which a second "elongated member" may be placed in order to convert this fence into a privacy fence. This requires that a second component be installed and therefore is inconvenient as compared to solutions which do not require the installation of this additional component.
Wong U.S. Pat. No. 4,124,198 describes a plastic fence having horizontally abutting sheets or panels which utilize "four keys extending from both sides of the sheet." Such an arrangement permits gaps to exist between the ends of each sheet and the mating "post section." Therefore this design is not completely effective as a privacy fence. By its design it's appearance is not that of a conventional wooden fence--this may further detract from its attractiveness as a substitute for wooden fencing.
A need therefore exists for an improved privacy fence which can reduce manufacturing costs, increase durability and increase isolation of an outdoor space against the intrusion of objectionable sounds, noises and curious persons.